<? 
$string="?a=1&b=2"; 

if (!false===parse_str($string))
	{ 
	// all is happy
	} 
else 	{ 
	// Whoops! error handling... 
	}

?> 

I would submit that to maintain the elegant conventions of PHP, it would be good to return 
A) The number of variables parsed (I'll leave in your court how to handle counting the # of array variables parsed) 

or 

B) false if the string was null, corrupt or "un-parsable". 

Currently, the only way to evaluate the success of this function is to know the last variable that is/should be in the input stream and check to see that THAT variable exists after running this function = less than optimum. 

Thanks!

-Ben